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Wiltsee, Christopher B.

Publications and source records attributed to Wiltsee, Christopher B..

Stratospheric Observatory for Infrared Astronomy (SOFIA) system concept

The system concept for the Stratospheric Observatory for Infrared Astronomy (SOFIA), as developed by NASA Ames Research Center is described. The SOFIA facility is a 3-meter class optical/infrared/submillimeter telescope mounted in an open cavity in the forebody of a Boeing 747 aircraft, to be operational in 1992. It represents the next generation of Ames' existing airborne IR facilities, and is about ten times more sensitive than the Kuiper Airborne Observatory (KAO) with 3 times better angular resolution, and able to detect all the far-infrared point sources discovered by IRAS (Infrared Astronomical Satellite) survey in 1983. Major requirements and design attributes of the SOFIA telescope are presented, along with a brief description of the Ground Support/Operations System.

Wiltsee, Christopher B.↗

Servicing operations for the SIRTF Observatory at the Space Station

This paper describes the servicing requirements, plans, and proposed Space Station-based servicing operations for the Space Infrared Telescope Facility (SIRTF) Observatory. SIRTF is a cryogenically-cooled, long-life, one meter class space telescope which will be operated by NASA as a free-flying observatory for infrared astronomy, in the mid-1990's. To achieve its 5-year lifetime requirement (10 year goal), SIRTF must be replenished periodically with cryogenic helium and have its life-limited modular subsystems replaced; capability for contingency repair of warm components will also be provided in the Observatory design. A general description of the SIRTF Observatory is given, including options for the support systems (spacecraft). The overall servicing philosophy and plans are addressed with scheduling and needed support elements described. A proposed Space Station-based servicing scenario is described, including orbital transfer, servicing and checkout operations. A detailed description and timeline for liquid helium replenishment operations is provided, including a conceptual design and technology development program for the cryogenic helium transfer dewar (tanker). Finally, a preliminary SIRTF spares/logistics philosophy is outlined, including tradeoffs to be considered.

Wiltsee, Christopher B.↗

The SIRTF mission

This paper describes the scientific and technical background and prospects for the Space Infrared Telescope Facility (SIRTF). SIRTF is a cryogenically-cooled, one meter-class space telescope which will be operated by NASA as an observatory for infrared astronomy, in the mid-1990's. SIRTF will provide detailed studies of even the faintest IRAS sources, important new capabilities for the study of known astrophysical phenomena, and the potential to make new and unexpected discoveries about the nature of the universe. The long-life SIRTF mission has undergone intensive review by the SIRTF Science Working Group, which was selected in mid-1984. This paper presents the outcome of that review process and describes the SIRTF program as it is now envisioned. Particular emphasis will be placed on the choice of orbit for SIRTF, the SIRTF scientific performance requirements, and the baseline design concept for the SIRTF facility and mission.

Werner, Michael W.↗